A study by scientists at Ohio State University published in the Journal of Family Issues has shown that siblings can be harmful to teenagers’ mental health. To reach this conclusion, the scientists gave questionnaires about their mental health to 9,400 14-year-olds in China and 9,100 peers in the United States. As it turned out, the happiest teenagers were those who had no siblings (China) or at most one.
As the scientists report, it didn’t matter whether the siblings were half or full siblings.
The smaller the age gap, the greater the effect
Interestingly, the age difference would have influenced the strength of the effect, the scientists write in their paper. The smaller the age difference between the siblings and the observed young person, the unhappier the latter was on average.
This observation may indicate that it is a kind of competition effect: the limited resource “parental attention” must be distributed among all children. Since children of similar ages usually have similar needs, the effect is more pronounced the smaller the age gap between the siblings is.
Study partly contradicts older literature
In the past, similar studies have sometimes led to very different results. As the “Süddeutsche Zeitung” reports, a team of scientists led by Gunda Herberth from the Helmholtz Center for Environmental Research showed in 2022 that children who have older siblings are less likely to develop behavioral problems.